1. Field
Embodiments of the invention relate generally to encryption and decryption of multimedia files, and more particularly, to a method and apparatus for encrypting/decrypting multimedia content to allow random access.
2. Background
As 3G and other cellular networks are deployed, new IP packet data based services are emerging. One of the most challenging service areas operators are seeking to exploit involves the distribution of video content to the mass market. High-quality video is the most data-intensive type of content. At the same time, consumer experience with current home viewing options presents operators and content providers with target markets that hold established ideas about what the user experience should be. The combination of consumer expectations and mobility present fundamental challenges to network operators and content providers. In summary, attractive business models, network control and management, access control, device capabilities and a compelling user experience combine to present a complex of interdependent challenges that have not been fully resolved in the wireless industry.
One challenge that has arisen is the need to provide protection of the content that is to be distributed. For example, the distributed content typically needs to be guarded from unauthorized copying. Further, content providers also wish to control, either directly or indirectly, the distribution of the content. Thus, content providers typically require that any content distribution system used by service providers have the ability to provide digital rights management (DRM), which refers to any of several technical arrangements that provide control for how distributed material can be used on any electronic device with such measures installed. An critical underlying component for all content distribution systems to support DRM so as to protect the intellectual property rights of content providers is the feature of encryption/decryption of media during transmission/receipt. In addition, there is often a requirement to store the media in an encrypted form, either on the servers at the distribution center or on the playback device. Further, the encryption often needs to support “trick” features such as the ability to view the content during fast-forward and rewind playback. It is desired that the media encryption solution should provide encryption with minimal changes to video coding interface.